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The Engineering of Landfills

practical.engineering

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Re: The Engineering of Landfills

#121

Post by bluGill »

renhanxue wrote: post #89
leoedin wrote: post #84

Earlier quoted context omitted.

What’s completely crazy about that is that there’s people spending serious money trying to build carbon sequestration systems while other people are turning an inert and stable form of carbon back into carbon dioxide in the name of sustainability.

Would you rather we'd burn peat (which is also sequestered carbon) instead? Because that's what we used to do. We need to stay warm in winter one way or another. In the 1950's we thought that in the future we'd have nuclear cogeneration plants. There was one such plant (Ågesta) in commercial operation, but it closed in the mid 1970's. edit: also, to your point about sequestration: it's in actual and literal fact the…

I'd prefer you use wind to get the energy(or solar but there isn't much sun when you need heat) and burn nothing.

Re: The Engineering of Landfills

#122

Post by gruez »

immibis wrote: post #85
daedrdev wrote: post #39

Earlier quoted context omitted.

Additionally, the top 10 rivers, 9 of which in Asia, produce an extremely high precent of land based ocean pollution

E.g. the bottles we sent them for "recycling"

That makes up a tiny amount of overall plastic waste.

>I estimate that a few percent of ocean plastics could result from trade from rich countries. A figure as high as 5% would not be unreasonable.

https://ourworldindata.org/plastic-waste-trade

Re: The Engineering of Landfills

#123

Post by cogman10 »

toomuchtodo wrote: post #106
scoofy wrote: post #99

Earlier quoted context omitted.

I genuinely use landfills, especially with plastic waste, as shibboleth to know whether I'm talking to somebody who is an environmentalist or somebody who is an "environmentalist." Anyone who thinks recycling plastic is some sort of normative good because "waste is bad" clearly hasn't put any thought into what environmental issues need to be focused on right now.

How do you feel about plasma gasification to ensure robust destruction of anything non-inert? I love landfills too! But humans are various shades of tricky, lazy, cost adverse, and untrustworthy (think limited liability) as it pertains to long term custodianship and management of things bad for people and the environment. TLDR You must engineer around the human. Potentially harmful physical matter that requires waste…

The big problem with plastic waste is getting it to the landfill (or incinerator) in the first place.

Once the plastics are captured, I don't see too much benefit in incinerating it beyond freeing up landfill space. But that's really not a major issue as you can always dig a deeper and wider landfill.

In fact, a major downside of incinerating the plastic is you end up with greenhouse gasses as a byproduct.

Re: The Engineering of Landfills

#124

Post by renhanxue »

yreg wrote: post #112
renhanxue wrote: post #88

Earlier quoted context omitted.

If we didn't burn waste we'd need to burn something else to stay warm in winter. Currently we supplement the waste with _mostly_ renewables, like byproducts from the forestry industry (e.g. treetops, wood chips, sawdust) and the olive oil industry (olive pits; we import this stuff from the Mediterranean region), but we burn a bit of peat too because there aren't enough reasonably priced renewables. Burning waste real…

> If we didn't burn waste we'd need to burn something else to stay warm in winter. Why not nuclear/renewables?

Nuclear was a thing in the 50's/60's but district heating isn't practical over long distances and nobody wanted nuclear plants in their suburbs.

Renewables we already do burn quite a bit of. But really, quite a lot of household waste is actually renewable too - cardboard packaging, food scraps that didn't end up in the compost, such things. So it's really not that bad.

Waste accounts for about 20% of the total energy required for heating in Sweden.

Re: The Engineering of Landfills

#125

Post by bluGill »

gruez wrote: post #113
flavius29663 wrote: post #63

Earlier quoted context omitted.

It was viable only because we were shipping "recyclables" that had to be "recycled" by contract, not pure garbage that could have just been buried. Sorting through that whole mess of "recyclables" was more expensive than shipping it to China and letting them just burn or bury it.

>Sorting through that whole mess of "recyclables" was more expensive than shipping it to China and letting them just burn or bury it. I thought they didn't bother and just buried it if it wasn't profitable. >GONZALEZ: Whoa. Oh, I've been doing that one wrong. So the city of Nogales went around to everyone's house this morning and picked up their recyclables. [...] And they brought them here. And where is all this goi…

> I thought they didn't bother and just buried it if it wasn't profitable.

The point is to cheat. Say you recycle and ensure that there are enough links in the chain nobody can follow it to the end and prove the stuff you ship to China wasn't recycled. China did recycle some stuff, but most of it wasn't. China decided to stop participating in that scam though.

Re: The Engineering of Landfills

#126

Post by toomuchtodo »

cogman10 wrote: post #123
toomuchtodo wrote: post #106

Earlier quoted context omitted.

How do you feel about plasma gasification to ensure robust destruction of anything non-inert? I love landfills too! But humans are various shades of tricky, lazy, cost adverse, and untrustworthy (think limited liability) as it pertains to long term custodianship and management of things bad for people and the environment. TLDR You must engineer around the human. Potentially harmful physical matter that requires waste…

The big problem with plastic waste is getting it to the landfill (or incinerator) in the first place. Once the plastics are captured, I don't see too much benefit in incinerating it beyond freeing up landfill space. But that's really not a major issue as you can always dig a deeper and wider landfill. In fact, a major downside of incinerating the plastic is you end up with greenhouse gasses as a byproduct.

Certainly, you are generating some greenhouse gasses in the process, which is a trade off to ensure immediate waste destruction. To note, you will have to flare methane from the landfill in perpetuity when landfilled. If one is so inclined, internalize the cost of direct air carbon capture into the cost of waste disposal for those emissions.

https://www.epa.gov/lmop/basic-information-about-landfill-ga...

> Municipal solid waste (MSW) landfills are the third-largest source of human-related methane emissions in the United States, accounting for approximately 14.4 percent of these emissions in 2022. The methane emissions from MSW landfills in 2022 were approximately equivalent to the greenhouse gas (GHG) emissions from more than 24.0 million gasoline-powered passenger vehicles driven for one year or the CO2 emissions from more than 13.1 million homes’ energy use for one year. At the same time, methane emissions from MSW landfills represent a lost opportunity to capture and use a significant energy resource.

TLDR Whether landfills or gasification, you are paying the piper regardless for emissions. Don't trust the human, pull forward the disposal.

Re: The Engineering of Landfills

#128

Post by [deleted] »

renhanxue wrote: post #89
leoedin wrote: post #84

Earlier quoted context omitted.

What’s completely crazy about that is that there’s people spending serious money trying to build carbon sequestration systems while other people are turning an inert and stable form of carbon back into carbon dioxide in the name of sustainability.

Would you rather we'd burn peat (which is also sequestered carbon) instead? Because that's what we used to do. We need to stay warm in winter one way or another. In the 1950's we thought that in the future we'd have nuclear cogeneration plants. There was one such plant (Ågesta) in commercial operation, but it closed in the mid 1970's. edit: also, to your point about sequestration: it's in actual and literal fact the…

[deleted]

Re: The Engineering of Landfills

#129

Post by ants_everywhere »

khaki54 wrote: post #81

I wonder if in 100-500 years they will mine landfills for materials or elements that have become scarce. Or maybe they will just keep them as natural gas reactors.

they'll certainly mine them for archaeological information.

that's one of the reasons I keep my trash in neat layers ordered chronologically

Re: The Engineering of Landfills

#130

Post by aziaziazi »

immibis wrote: post #85
daedrdev wrote: post #39

Earlier quoted context omitted.

Additionally, the top 10 rivers, 9 of which in Asia, produce an extremely high precent of land based ocean pollution

E.g. the bottles we sent them for "recycling"

For the sake of analogy: or the sea food we buy from them
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